- Thumbtack
A thumbtack (known as a pushpin or a drawing-pin in the UK,
India ,Australia andNew Zealand ) is a short nail or pin with a large, slightly rounded head made of metal which is used to fasten documents to a background for public display and which can easily be inserted or removed by hand.Types of thumbtack
The most common piecemealed thumbtacks are made by attaching a
brass stem to a flat brass head. Some have colouredplastic tops, to make them more attractive.Map pins, or push pins, are also a type of thumbtack. Map pins have a handle-like cover of plastic, which brings the pin out of the wall, allowing quick and easy removal from surfaces. Some other map pins have a round 1mm head to allow for easy removal. Both types come in a variety of colors. Map pins are safer than flat-headed thumbtacks when dropped on the ground or discarded on a surface, since they will not normally rest with the point upward.
History
The map pin was invented by
Edwin Moore around 1900, the year in which he founded theMoore Push-Pin Company [http://www.push-pin.com/mpphist1.html] .As far as is currently known, the thumbtack was invented by the clockmaker
Johann Kirsten in the year 1903 in the town ofLychen inUckermark ,Germany [http://72.14.207.104/search?q=cache:mowzVYM9mkoJ:www.berlin-partner.de/index.php%3Fpage%3D332%26modaction%3DshowItem%26id%3D161++Johann+Kirsten+thumbtack&hl=en&gl=au&ct=clnk&cd=6] . He sold the rights to the invention toOtto Lindstedt , a businessman, who received apatent for the thumbtack on 8th January 1904. Lindstedt became a wealthy man while Kirsten, the clockmaker, remained in poverty.Other sources ascribe the invention of the thumbtack to
Austria n factory ownerHeinrich Sachs in 1888 [http://www.sax.info/en/lex-e/Firmenchronik-e.html] .Physics
A thumbtack can be inserted by hand because of the large
area of its head relative to the area of its point. When a relatively lowpressure is applied across the large head of a thumbtack, a high pressure will be applied by the tip of the thumbtack. The low pressure on the head means the thumbtack will not pierce a person's finger. The high pressure at the tip allows it to pierce the surface to which the document is being fastened.The thumb tack has a flat head in order to place the thumb, where as the drawing pin has a longer head which is gripped between two fingers to place.
Wikimedia Foundation. 2010.